| RefNo | Title | Date |
| EC/1868/12 | Duncan, Peter Martin: certificate of election to the Royal Society | |
| IM/001215 | Duncan, Peter Martin | nd |
| NLB/4/443 | Copy letter from Herbert Rix, to Professor Peter Martin Duncan, Fellow of the Royal Society, Chairman | 2 June 1890 |
| NLB/4/215 | Copy letter from Herbert Rix, to Dr Peter Martin Duncan, Fellow of the Royal Society | 14 March 1890 |
| NLB/3/692 | Copy letter from Herbert Rix, to Dr Peter Martin Duncan, Fellow of the Royal Society | 17 September 1889 |
| NLB/5/351 | Copy letter from Herbert Rix, to Dr [Peter Martin] Duncan, [Fellow of the Royal Society] | 22 May 1891 |
| NLB/3/988 | Copy letter from Herbert Rix, to Dr Peter Martin Duncan, Fellow of the Royal Society | 2 December 1889 |
| NLB/5/375 | Copy letter from Theodore E James, to Messrs Harrison & Sons | 1 June 1891 |
| NLB/5/369 | Copy letter from Herbert Rix, to Dr Woodward, Fellow of the Royal Society | 29 May 1891 |
| NLB/5/922 | Copy letter from Herbert Rix, to Sir William Thomson, President of the Royal Society | 16 November 1891 |
| RR/7/93 | Referee's report by George Busk, on a paper 'On the structure and affinities of guynia annulata, dunc., with remarks upon the persistence of palaeozoic types of madreporaria' by Peter Martin Duncan | 25 November 1871 |
| RR/7/24 | Referee's report by Peter Martin Duncan, on a paper 'On the pre-carboniferous flora of Northeastern America' by Dawson | 11 May 1870 |
| RR/7/298 | Referee's report by George Busk, on a paper 'On the nervous system of actinia - Part I' by Peter Martin Duncan | 17 March 1874 |
| RR/6/91 | Referee's report by Peter Martin Duncan, on a paper 'Description of Parkeria and Loftusia, two gigantic types of arenaceous foraminifera' by William Benjamin Carpenter and Henry Bowman Brady | 20 July 1869 |
| RR/7/124 | Letter from Peter Martin Duncan, on a paper 'On the fossil mammals of Australia.—Part IV. Dentition and mandible of thylacoleo carnifex, with remarks on the arguments for its herbivority' by Richard Owen | 2 February 1871 |
| RR/7/129 | Referee's report by Peter Martin Duncan, on a paper 'On the fossil mammals of Australia - Part V. Genus nototherium' by Richard Owen | 14 September 1871 |
| RR/7/296 | Referee's report by George James Allman, on a paper 'On the nervous system of actinia - Part I' by Peter Martin Duncan | 15 January 1874 |
| RR/7/91 | Referee's report by Thomas Henry Huxley, on a paper 'On the structure and affinities of guynia annulata, dunc., with remarks upon the persistence of palaeozoic types of madreporaria' by Peter Martin Duncan | 29 July 1871 |
| RR/6/106 | Letter from Peter Martin Duncan, to William Allen Miller, regarding a paper 'On the genera Heterophyllia, Battersbyia, Palaecyclus, and Asterosmilia; the anatomy of their species, and their position in the classification of sclerodermic zoantharia' by Peter Martin Duncan | 30 October 1867 |
| RR/7/191 | Referee's report by Peter Martin Duncan, on a paper 'On the fossil mammals of Australia - Part VII. Genus phascolomys: species exceeding the existing ones in size' by Richard Owen | 26 June 1872 |
| RR/7/131 | Referee's report by Peter Martin Duncan, on a paper 'On the structure and development of the skull of the common frog' by William Kitchen Parker | 24 February 1871 |
| RR/7/127 | Letter from Peter Martin Duncan, on a paper 'On the fossil mammals of Australia.—Part IV. Dentition and mandible of thylacoleo carnifex, with remarks on the arguments for its herbivority' by Richard Owen | 13 April 1871 |
| RR/7/122 | Referee's report by Peter Martin Duncan, on a paper 'On the fossil mammals of Australia.—Part IV. Dentition and mandible of thylacoleo carnifex, with remarks on the arguments for its herbivority' by Richard Owen | 5 January 1871 |
| RR/7/455 | Referee's report by Peter Martin Duncan, on a paper 'On the structure of a species of millepora occurring at Tahiti, Society Islands' by Henry Nottidge Moseley | 8 May 1876 |
| RR/9/126 | Referee's report by Peter Martin Duncan, on a paper 'On a new crinoid from the Southern Sea' by Philip Herbert Carpenter | 4 September 1883 |
| RR/9/281 | Referee's report by Peter Martin Duncan, on a paper 'On beds of sponge-remains in the lower and upper greensand of the South of England' by George Jennings Hinde | 11 August 1885 |
| RR/8/106 | Referee's report by Peter Martin Duncan, on a paper 'Notes on Physical Geology' by Samuel Haughton | 25 April 1878 |
| RR/6/104 | Referee's report by George Busk, on a paper 'On the genera Heterophyllia, Battersbyia, Palaecyclus, and Asterosmilia; the anatomy of their species, and their position in the classification of sclerodermic zoantharia' by Peter Martin Duncan | 19 June 1867 |
| NLB/4/1053 | Copy letter from Herbert Rix, to Dr Peter Martin Duncan, Fellow of the Royal Society | 6 January 1891 |
| RR/7/198 | Referee's report by Peter Martin Duncan, on a paper 'Report on the exploration of Brixham Cave conducted by a committee of the Geological Society, and under the superintendence of Wm. Pengelly, Esq., F. R. S., aided by a local Committee; with descriptions of the animal remains by George Busk, Esq., F.R.S., and of the Flint implements by John Evans, Esq., F.R.S' by Joseph Prestwich, George Busk and John Evans | 13 April 1872 |
| RR/6/107 | Referee's report by William Benjamin Carpenter, on a paper 'On Palaeocoryne, a genus of tubularine hydrozoa from the Carboniferous formation' by Peter Martin Duncan and H M Jenkins | 3 August 1869 |
| RR/6/105 | Referee's report by William Benjamin Carpenter, on a paper 'On the genera Heterophyllia, Battersbyia, Palaecyclus, and Asterosmilia; the anatomy of their species, and their position in the classification of sclerodermic zoantharia' by Peter Martin Duncan | 20 June 1867 |
| MC/8/92 | Letter from P [Peter] Martin Duncan, 48 Lee Terrace, Lee, to W [Walter] White, [Assistant Secretary of the Royal Society] | 22 October 1867 |
| RR/7/188 | Referee's report by Peter Martin Duncan, on a paper 'On the fossil mammals of Australia - Part VI. Genus phascolomys' by Richard Owen | 11 March 1872 |
| RR/7/258 | Referee's report by Peter Martin Duncan, on a paper 'Contributions to the study of the errant annelides of the older palaeozoic rocks' by Henry Alleyne Nicholson | 2 December 1873 |
| MC/8/98 | Letter from E M Williams, Carshalton, Surrey, to W [Walter] White, [Assistant Secretary of the Royal Society] | 28 October 1867 |
| MC/8/94 | Letter from P [Peter] Martin Duncan, 48 Lee Terrace, Lee, to E M Williams, [lithographer] | 22 October 1867 |
| MC/8/104 | Letter from P [Peter] Martin Duncan, Geological Society, Somerset House, to Wm [William] Allen Miller, Treasurer of the Royal Society | 8 November 1867 |
| AP/60/7 | Unpublished paper, 'On Astrophiura permira, an echinoderm-form intermediate between Ophiuroidea and Asteroidea' by W [Walter] Percy Sladen | 1878 |
| AP/60/7/1 | Unpublished manuscript, 'On Astrophiura permira, an echinoderm-form intermediate between Ophiuroidea and Asteroidea' by W [Walter] Percy Sladen | 1878 |
| RR/7/92 | Referee's report by Phillip de Malpas Egerton, on a paper 'On the structure and affinities of guynia annulata, dunc., with remarks upon the persistence of palaeozoic types of madreporaria' by Peter Martin Duncan | 29 July 1871 |
| RR/6/195 | Letter from Thomas Henry Huxley, to George Gabriel Stokes, regarding a paper 'On the genera heterophyllia, battersbyia, palæcyclus, and asterosmilia; the anatomy of their species, and their position in the classification of sclerodermic zoantharia' by Peter Martin Duncan | 21 October 1867 |
| RR/8/313 | Referee's report by Peter Martin Duncan, on an untraced paper 'On the formation of shells' by Green | 7 March 1881 |
| MC/8 | Volume 8 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1867-1869 |
| RR/6/287 | Letter from Henry B Wheatley, to George Gabriel Stokes, regarding two papers 'On Holtenia, a genus of vitreous sponges' by Charles Thomas Wyville Thomson and 'On Palaeocoryne, a genus of tubularine hydrozoa from the Carboniferous formation' by Peter Martin Duncan and H M Jenkins | 3 September 1869 |
| RR/6/289 | Referee's report by Henry John Carter, on two papers 'On Holtenia, a genus of vitreous sponges' by Charles Thomas Wyville Thomson and 'On Palaeocoryne, a genus of tubularine hydrozoa from the Carboniferous formation' by Peter Martin Duncan and H M Jenkins | 9 August 1869 |
| RR/6/108 | Letter from Peter Martin Duncan, to George Gabriel Stokes, regarding a paper 'On Palaeocoryne, a genus of tubularine hydrozoa from the Carboniferous formation' by Peter Martin Duncan and H M Jenkins | 6 September 1869 |
| RR/6/196 | Letter from Peter Martin Duncan, to George Gabriel Stokes, regarding a paper 'On the genera heterophyllia, battersbyia, palæcyclus, and asterosmilia; the anatomy of their species, and their position in the classification of sclerodermic zoantharia' by Peter Martin Duncan | 25 July 1867 |
| RR/7/297 | Referee's report by George James Allman, on a paper 'On the nervous system of actinia - Part I' by Peter Martin Duncan | 24 February 1874 |
| RR/8/37 | Referee's report by Peter Martin Duncan, on a paper 'On the nature and origin of the beds of chert in the upper carboniferous limestones of Ireland' by Edward Hull and E T Hardman | 30 May 1877 |